First of all im new to the forum thanks for having me ! I have a serious issue with my truck its a 93 pickup 4cyl 5spd and it has a idle and acceleration problem big time !!!! Mostly at idle and around 2000 rpms its like not even drive able and its my DD!!! Here are some thing ive tried/replaced
Fuel pump
Fuel filter
Open circuit relay
Have tried 2 differnet computer
Have tried 2different afm
Have replaced tps (not 100% the adjust is correct)
Head gasket
Coolant temp sensor
Vaccum leaks
Trottle body cleaned
Valves adjusted
Cap
Rotor
Plugs an wires
Coil
Cleaned injectors and changed orings
Fuel pressure regulator

Checked ground but im missing the one on the power steerin mount any pics or info on that ??? Where it comes from what color it is ?

Im sure im missing some stuff but im lost and really need this truck to run any ideas help please ??? I seriously will paypal someone money if they can pin point my problem

Thanks stan. If you got time give me a call or text and we can try to figure it out it 321-356-0889

 

Also has upgraded exhaust and a cold air intake
Also changed o2 sensor

 

What O2 sensor did you use? Is it one that was a direct replacement, or did you have to wire it?

 

What exactly is the problem you're having? You said you have issues at idle and around 2k RPMs, but you didn't say what the actual problem is. Can you be more specific about what it's doing?

 

did you adjust the idle screw on the throttle body?? any codes??

 

O2 sensor was the wire it in your self type

Idle idle screw does nothing and no codes the only 2 recent codes were afm and tps wihich i tried 2 diffenert afm and have a brand new tps i got yesterday anyone walk me threw the steps on adjusting it ? I tried looking at 4 wheel crawlings link and its really confusing


And at idle it barly runs at all like its running out of gas or missing and on acceration it acts like its running on fumes jerking and kicking and hopping but if its around 3000-5000 it will run like a champ free reving or driving ??? It started as a little miss or stumble now going even more down hill

 

Yesterday i also pulled the valve cover and made sure all valves were hitting and checked the timing

 

check compression?

 

If you're not sure your TPS is set correctly, I'd start with making sure that's right before you go chasing another possible phantom. Unplug the TPS. Did anything change?

Without having the specs for your particular model/TPS in front of me, it's hard to walk you thru it. You have to get all the different readings within range and on some of them you have to use feeler gauges between the throttle stop screw and plate. OH, make sure you're throttle stop screw is set right first! Loosen the locking nut on it and back off the screw until it's not touching the stop plate anymore. Then screw it back in until it just touches the plate. After that, give it another 1/4 turn in and then set the locking nut in place. You may already know that, but it's easier to go ahead and tell you than for you to have to ask and then wait for another answer if you don't already know.

 

Ive done the idle stop screw adjustment and when i unplug it it idles worse. Rpms drop a couple humdred. I understand you put the feeler gauage in between the throttle plat and idle stop screw but what size gauage is it ? And i have all the measurements and number written down so i know which connections to test and what the out come should be.
Thanks for the reply!

 

Yes compression is all good

 

when you say the idle screw does nothing, it makes me wonder if the o ring around screw is cut or broken. pull the screw all the way out and inspect the oring

 

What i ment to say is it doesnt help it dose idle it up and down but i pulled it anyways its there looks alittle flattened but no rips im pulling the valve cover to check/readjust valve now and also gonna do another compression test

 

Check out 4crawler.com for the specifics on setting your TPS. Also do a search around YotaTech. You'll find plenty of info about it here too. There's a couple different feeler gauge sizes you have to use to get it set right. I want to say it's a .5something mm for one setting and .85 mm for another setting. There are 4 settings in all. I know one is fully closed and another is WOT. Double-check the feeler gauge sizes for the remaining 2 tests and what points to test between for each of the tests. It's really not hard, just time consuming for what it is. I did mine in about 30 minutes start to finish.

 

http://www.lcengineering.com/LCTechP...Adjustment.pdf

This is the info i used to do the tps setting

Here are the results
Test 1 0.53
Test 2. 0.02
Test 3. 0.02
Test 4. 4.76
Test 5. 6.12.

Sound like i got it ? I know test two should be infint/open but thats about the closest i got it

I also just readjusted the valves and checked toming again timing is good its were its always been. Valves didnt help just made it alittle quieter.

 

No. 0.020 kohms is not close to "infinite/open."

Setting Idl-E2 to open when the throttle is open "a little" (arbitrarily, 0.80mm) is actually the only adjustment there is. (the other "tests" are just to verify the TPS is not completely wrecked.) So yours is not adjusted.

With your meter reading kohms, you want Idl-E2 to be shorted (your 0.020 kohms is fine; anything less than 2.3 kohms is considered to be shorted for purposes of this test) when the throttle is closed, open when the throttle is opened. That's all there is to it.

 

Ok so i need to get test 3 to open/infinite not .02 ?
Which test idl and e2 ?
Thanks

 

http://personal.utulsa.edu/~nathan-buchanan/93fsm/

read this

 

There is alot of good info there thanks man !!!! But is it as simple as getting the test to open/infinte on test 3 ?

 

keep that link and save it in your favorites